There are more than 700 named varieties of crabapples--all prodigious bloomers that cover themselves in white, pink, or red flowers in spring. They are beautiful small trees for sunny gardens, hardy and reliable. Crabapples have stately, even dramatic structure, but they benefit from occasional pruning. They are excellent wildlife trees. When they bloom, bees and other pollinators make the trees fairly buzz with life. Look for cultivars with resistance to fire blight and apple scab. Bell, an expert on crabapples, advises asking local extension agents for their recommendations for your area. The best crabapples for birds, Kress says, are small-fruited cultivars that hold their fruit into winter, including 'Bob White' and 'Donald Wyman'. Most grow 15 to 25 feet tall. Hardy in Zones 4 to 7.